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JavaScript: Create a new string from a given string, removing the first and last characters of the string if the first or last character are 'P'

JavaScript Basic: Exercise-67 with Solution

Write a JavaScript program to create a new string from a given string, removing the first and last characters of the string if the first or last character are 'P'. Return the original string if the condition is not satisfied.

Pictorial Presentation:

JavaScript: Create a new string from a given string, removing the first and last characters of the string if the first or last character are 'P'

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JavaScript program to create a new string from a given string, removing the first and last characters of the string if the first or  last character are �P</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function nop(str) {
  let start_pos = 0;
  let end_pos = str.length;

  if (str.length > 0 && str.charAt(0) == 'P') 
    { 
      start_pos = 1; 
    }

  if (str.length > 1 && str.charAt(str.length - 1) == 'P') 
  {
    end_pos--;
  }

  return str.substring(start_pos, end_pos);
}

console.log(nop("PythonP"));
console.log(nop("Python"));
console.log(nop("JavaScript"));

Sample Output:

ython
ython
JavaScript

Flowchart:

Flowchart: JavaScript - Create a new string from a given string, removing the first and last characters of the string if the first or last character are 'P'

ES6 Version:

function nop(str) {
  let start_pos = 0;
  let end_pos = str.length;

  if (str.length > 0 && str.charAt(0) == 'P') 
    { 
      start_pos = 1; 
    }

  if (str.length > 1 && str.charAt(str.length - 1) == 'P') 
  {
    end_pos--;
  }

  return str.substring(start_pos, end_pos);
}

console.log(nop("PythonP"));
console.log(nop("Python"));
console.log(nop("JavaScript"));

Live Demo:

See the Pen JavaScript - removing the first and last characters of the string if the first or last character are P - basic-ex-67 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript program to display the city name if the string begins with "Los" or "New" otherwise return blank.
Next: Write a JavaScript program to create a new string taking the first and last n characters from a given string.

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JavaScript: Tips of the Day

Classes/function constructors

class Person {
  constructor() {
    this.name = 'Owen';
  }
}

Person = class AnotherPerson {
  constructor() {
    this.name = 'Eddie';
  }
};

const member = new Person();
console.log(member.name);

We can set classes equal to other classes/function constructors. In this case, we set Person equal to AnotherPerson. The name on this constructor is Eddie, so the name property on the new Person instance member is "Eddie".

Ref: https://bit.ly/3jFRBje